OverviewCorteo Peak is an impressive peak, especially from the east near Maple Pass. It is located 1.8 miles southeast of Black Peak. Corteo is a double-summited peak (south peak is taller), and all sides of the peak are quite steep. There are two main routes (the Beckey guide mentions a third), the east face and the southwest ridge. Both routes are accessed by the Heather Pass/Maple Pass trail. The east face route is shorter, but more difficult. The southwest route is easy to combine with Black Peak via the Lewis Glacier. The Lewis Glacier is basically non-existent now, but makes a good route in the early season.
Getting ThereDrive Highway 20 (North Cascades Highway) to Rainy Pass and park at the trailhead for Maple Pass (on the west side of the highway). Hike the Maple Pass trail to a junction with the Lake Ann trail, and continue on the Maple Pass trail. If taking the east face route, continue to Maple Pass. If taking the southwest ridge route, take the side-trail to Heather Pass.
Southwest Ridge Route
East Face Route